# Copyright (C) 2006 - Steve Frécinaux
#            2016-17 - Nick Boultbee
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.

# Parts from "Interactive Python-GTK Console"
# (stolen from epiphany's console.py)
#     Copyright (C), 1998 James Henstridge <james@daa.com.au>
#     Copyright (C), 2005 Adam Hooper <adamh@densi.com>
# Bits from gedit Python Console Plugin
#     Copyright (C), 2005 Raphaël Slinckx

# PythonConsole taken from totem
# Plugin parts:
# Copyright 2009,2010,2013 Christoph Reiter
#                     2016 Nick Boultbee


import sys
import re
import traceback

from gi.repository import Gtk, Pango, Gdk, GLib

from quodlibet import _, app, ngettext
from quodlibet import const
from quodlibet.plugins.events import EventPlugin
from quodlibet.plugins.gui import UserInterfacePlugin
from quodlibet.qltk import Icons, add_css, Align
from quodlibet.plugins.songsmenu import SongsMenuPlugin
from quodlibet.util.collection import Collection
from quodlibet.util import print_


class PyConsole(SongsMenuPlugin):
    PLUGIN_ID = 'Python Console'
    PLUGIN_NAME = _('Python Console')
    PLUGIN_DESC = _('Interactive Python console. Opens a new window.')
    PLUGIN_ICON = Icons.UTILITIES_TERMINAL

    def plugin_songs(self, songs):
        desc = ngettext("%d song", "%d songs", len(songs)) % len(songs)
        win = ConsoleWindow(create_console(songs), title=desc)
        win.set_icon_name(self.PLUGIN_ICON)
        win.set_title(_("{plugin_name} for {songs} ({app})").format(
            plugin_name=self.PLUGIN_NAME, songs=desc, app=app.name))
        win.show_all()


class PyConsoleSidebar(EventPlugin, UserInterfacePlugin):
    PLUGIN_ID = 'Python Console Sidebar'
    PLUGIN_NAME = _('Python Console Sidebar')
    PLUGIN_DESC = _('Interactive Python console sidebar, '
                    'that follows the selected songs in the main window.')
    PLUGIN_ICON = Icons.UTILITIES_TERMINAL

    def enabled(self):
        self.console = create_console()

    def plugin_on_songs_selected(self, songs):
        self.console.namespace = namespace_for(songs)

    def create_sidebar(self):
        align = Align(self.console)
        self.sidebar = align
        self.sidebar.show_all()
        return align


def create_console(songs=None):
    console = PythonConsole(namespace_for(songs)) if songs else PythonConsole()
    access_string = _("You can access the following objects by default:")
    access_string += "\\n".join([
                    "",
                    "  %5s: SongWrapper objects",
                    "  %5s: Song dictionaries",
                    "  %5s: Filename list",
                    "  %5s: Songs Collection",
                    "  %5s: Application instance"]) % (
                       "songs", "sdict", "files", "col", "app")

    dir_string = _("Your current working directory is:")

    console.eval("import mutagen", False)
    console.eval("import os", False)
    console.eval("print(\"Python: %s / Quod Libet: %s\")" %
                 (sys.version.split()[0], const.VERSION), False)
    console.eval("print(\"%s\")" % access_string, False)
    console.eval("print(\"%s \"+ os.getcwd())" % dir_string, False)
    return console


def namespace_for(song_wrappers):
    files = [song('~filename') for song in song_wrappers]
    song_dicts = [song._song for song in song_wrappers]
    collection = Collection()
    collection.songs = song_dicts
    return {
        'songs': song_wrappers,
        'files': files,
        'sdict': song_dicts,
        'col': collection,
        'app': app}


class ConsoleWindow(Gtk.Window):
    def __init__(self, console, title=None):
        Gtk.Window.__init__(self)
        if title:
            self.set_title(title)
        self.add(console)
        self.set_size_request(700, 500)
        console.connect("destroy", lambda *x: self.destroy())


class PythonConsole(Gtk.ScrolledWindow):
    def __init__(self, namespace=None, destroy_cb=None):
        Gtk.ScrolledWindow.__init__(self)

        self.destroy_cb = destroy_cb
        self.set_policy(Gtk.PolicyType.NEVER, Gtk.PolicyType.AUTOMATIC)
        self.set_shadow_type(Gtk.ShadowType.NONE)
        self.view = Gtk.TextView()
        add_css(self, "* { background-color: white; padding: 6px; } ")
        self.view.modify_font(Pango.font_description_from_string('Monospace'))
        self.view.set_editable(True)
        self.view.set_wrap_mode(Gtk.WrapMode.CHAR)
        self.add(self.view)
        self.view.show()

        buffer = self.view.get_buffer()
        self.normal = buffer.create_tag("normal")
        self.error = buffer.create_tag("error")
        self.error.set_property("foreground", "red")
        self.command = buffer.create_tag("command")
        self.command.set_property("foreground", "blue")

        self.__spaces_pattern = re.compile(r'^\s+')
        self.namespace = namespace or {}

        self.block_command = False

        # Init first line
        buffer.create_mark("input-line", buffer.get_end_iter(), True)
        buffer.insert(buffer.get_end_iter(), ">>> ")
        buffer.create_mark("input", buffer.get_end_iter(), True)

        # Init history
        self.history = ['']
        self.history_pos = 0
        self.current_command = ''
        self.namespace['__history__'] = self.history

        # Set up hooks for standard output.
        self.stdout = OutFile(self, self.normal)
        self.stderr = OutFile(self, self.error)

        # Signals
        self.view.connect("key-press-event", self.__key_press_event_cb)
        buffer.connect("mark-set", self.__mark_set_cb)

    def __key_press_event_cb(self, view, event):
        modifier_mask = Gtk.accelerator_get_default_mod_mask()
        event_state = event.state & modifier_mask

        if event.keyval == Gdk.KEY_d and \
                        event_state == Gdk.ModifierType.CONTROL_MASK:
            self.destroy()

        elif event.keyval == Gdk.KEY_Return and \
                        event_state == Gdk.ModifierType.CONTROL_MASK:
            # Get the command
            buffer = view.get_buffer()
            inp_mark = buffer.get_mark("input")
            inp = buffer.get_iter_at_mark(inp_mark)
            cur = buffer.get_end_iter()
            line = buffer.get_text(inp, cur, True)
            self.current_command = self.current_command + line + "\n"
            self.history_add(line)

            # Prepare the new line
            cur = buffer.get_end_iter()
            buffer.insert(cur, "\n... ")
            cur = buffer.get_end_iter()
            buffer.move_mark(inp_mark, cur)

            # Keep indentation of preceding line
            spaces = re.match(self.__spaces_pattern, line)
            if spaces is not None:
                buffer.insert(cur, line[spaces.start():spaces.end()])
                cur = buffer.get_end_iter()

            buffer.place_cursor(cur)
            GLib.idle_add(self.scroll_to_end)
            return True

        elif event.keyval == Gdk.KEY_Return:
            # Get the marks
            buffer = view.get_buffer()
            lin_mark = buffer.get_mark("input-line")
            inp_mark = buffer.get_mark("input")

            # Get the command line
            inp = buffer.get_iter_at_mark(inp_mark)
            cur = buffer.get_end_iter()
            line = buffer.get_text(inp, cur, True)
            self.current_command = self.current_command + line + "\n"
            self.history_add(line)

            # Make the line blue
            lin = buffer.get_iter_at_mark(lin_mark)
            buffer.apply_tag(self.command, lin, cur)
            buffer.insert(cur, "\n")

            cur_strip = self.current_command.rstrip()

            if (cur_strip.endswith(":") or
                (self.current_command[-2:] != "\n\n" and self.block_command)):
                # Unfinished block command
                self.block_command = True
                com_mark = "... "
            elif cur_strip.endswith("\\"):
                com_mark = "... "
            else:
                # Eval the command
                self.__run(self.current_command)
                self.current_command = ''
                self.block_command = False
                com_mark = ">>> "

            # Prepare the new line
            cur = buffer.get_end_iter()
            buffer.move_mark(lin_mark, cur)
            buffer.insert(cur, com_mark)
            cur = buffer.get_end_iter()
            buffer.move_mark(inp_mark, cur)
            buffer.place_cursor(cur)
            GLib.idle_add(self.scroll_to_end)
            return True

        elif event.keyval == Gdk.KEY_KP_Down or event.keyval == Gdk.KEY_Down:
            # Next entry from history
            view.emit_stop_by_name("key_press_event")
            self.history_down()
            GLib.idle_add(self.scroll_to_end)
            return True

        elif event.keyval == Gdk.KEY_KP_Up or event.keyval == Gdk.KEY_Up:
            # Previous entry from history
            view.emit_stop_by_name("key_press_event")
            self.history_up()
            GLib.idle_add(self.scroll_to_end)
            return True

        elif event.keyval == Gdk.KEY_KP_Left or \
                        event.keyval == Gdk.KEY_Left or \
                        event.keyval == Gdk.KEY_BackSpace:
            buffer = view.get_buffer()
            inp = buffer.get_iter_at_mark(buffer.get_mark("input"))
            cur = buffer.get_iter_at_mark(buffer.get_insert())
            return inp.compare(cur) == 0

        elif event.keyval == Gdk.KEY_Home:
            # Go to the begin of the command instead of the begin of the line
            buffer = view.get_buffer()
            inp = buffer.get_iter_at_mark(buffer.get_mark("input"))
            if event_state == Gdk.ModifierType.SHIFT_MASK:
                buffer.move_mark_by_name("insert", inp)
            else:
                buffer.place_cursor(inp)
            return True

    def __mark_set_cb(self, buffer, iter, name):
        input = buffer.get_iter_at_mark(buffer.get_mark("input"))
        pos = buffer.get_iter_at_mark(buffer.get_insert())
        self.view.set_editable(pos.compare(input) != -1)

    def get_command_line(self):
        buffer = self.view.get_buffer()
        inp = buffer.get_iter_at_mark(buffer.get_mark("input"))
        cur = buffer.get_end_iter()
        return buffer.get_text(inp, cur, True)

    def set_command_line(self, command):
        buffer = self.view.get_buffer()
        mark = buffer.get_mark("input")
        inp = buffer.get_iter_at_mark(mark)
        cur = buffer.get_end_iter()
        buffer.delete(inp, cur)
        buffer.insert(inp, command)
        buffer.select_range(buffer.get_iter_at_mark(mark),
                            buffer.get_end_iter())
        self.view.grab_focus()

    def history_add(self, line):
        if line.strip() != '':
            self.history_pos = len(self.history)
            self.history[self.history_pos - 1] = line
            self.history.append('')

    def history_up(self):
        if self.history_pos > 0:
            self.history[self.history_pos] = self.get_command_line()
            self.history_pos -= 1
            self.set_command_line(self.history[self.history_pos])

    def history_down(self):
        if self.history_pos < len(self.history) - 1:
            self.history[self.history_pos] = self.get_command_line()
            self.history_pos += 1
            self.set_command_line(self.history[self.history_pos])

    def scroll_to_end(self):
        iter = self.view.get_buffer().get_end_iter()
        self.view.scroll_to_iter(iter, 0.0, False, 0.5, 0.5)
        return False

    def write(self, text, tag=None):
        buf = self.view.get_buffer()
        if tag is None:
            buf.insert(buf.get_end_iter(), text)
        else:
            buf.insert_with_tags(buf.get_end_iter(), text, tag)

        GLib.idle_add(self.scroll_to_end)

    def eval(self, command, display_command=False):
        buffer = self.view.get_buffer()
        lin = buffer.get_mark("input-line")
        buffer.delete(buffer.get_iter_at_mark(lin),
                      buffer.get_end_iter())

        if isinstance(command, list) or isinstance(command, tuple):
            for c in command:
                if display_command:
                    self.write(">>> " + c + "\n", self.command)
                self.__run(c)
        else:
            if display_command:
                self.write(">>> " + c + "\n", self.command)
            self.__run(command)

        cur = buffer.get_end_iter()
        buffer.move_mark_by_name("input-line", cur)
        buffer.insert(cur, ">>> ")
        cur = buffer.get_end_iter()
        buffer.move_mark_by_name("input", cur)
        self.view.scroll_to_iter(buffer.get_end_iter(), 0.0, False, 0.5, 0.5)

    def __run(self, command):
        sys.stdout, self.stdout = self.stdout, sys.stdout
        sys.stderr, self.stderr = self.stderr, sys.stderr

        try:
            try:
                r = eval(command, self.namespace, self.namespace)
                if r is not None:
                    print_(repr(r))
            except SyntaxError:
                exec(command, self.namespace)
        except:
            if hasattr(sys, 'last_type') and sys.last_type == SystemExit:
                self.destroy()
            else:
                traceback.print_exc()

        sys.stdout, self.stdout = self.stdout, sys.stdout
        sys.stderr, self.stderr = self.stderr, sys.stderr


class OutFile(object):
    """A fake output file object. It sends output to a TK test widget,
    and if asked for a file number, returns one set on instance creation"""

    def __init__(self, console, tag):
        self.console = console
        self.tag = tag

    def close(self):
        pass

    def flush(self):
        pass

    def fileno(self):
        raise IOError

    def isatty(self):
        return 0

    def read(self, a):
        return ''

    def readline(self):
        return ''

    def readlines(self):
        return []

    def write(self, s):
        self.console.write(s, self.tag)

    def writelines(self, l):
        self.console.write(l, self.tag)

    def seek(self, a):
        raise IOError(29, 'Illegal seek')

    def tell(self):
        raise IOError(29, 'Illegal seek')

    truncate = tell
